The invention relates generally to machining of an advanced material, and in particular to hybrid machining a contoured workpiece with thin walls, such as an airfoil of a gas turbine engine.
Contoured metal parts with thin walls are often difficult and costly to machine. Cost is increased when the parts are made from specialized alloys, such as titanium alloys and the like. Such parts often cannot be accurately cast without needing some final finish machining operation. Moreover, precision casting adds significant cost to even relatively simple shapes. Under certain circumstances, parts are produced from an oversized metal stock and machined to final form with a technique known as stab milling. This process is intensive with respect to total machining time, tooling cost, and often requires specialized fixturing particularly when the part has thin walls or is flimsy. Thus, it is desirable to provide an alternative method that addresses cutting time, machine time, tooling cost and fixturing.